Combining ability studies in China aster (Callistephus chineriswi (L.) Nees.)

A diallel analysis was carried out (excluding reciprocals) with a view to estimate combining ability effects for yield and its components in China aster (Callistephus chinensis (L.) Nees) involving six diverse parental lines. Significant differences in the mean squares due to gca and sca for all the characters except number of primary branches indicated the presence of sufficient variability in the combining ability of the parents used. The high magnitude of gca mean squares than the sca mean squares indicated predominant role of additive gene action. Parents recorded significant general combining ability effects for 13 characters out of 15 characters. Parents P.G. Pink (P₄) and P.G. White (P₆) were good general combiners for yield and yield attributes and P₁ for earliness of flowering. The cross combination P.G. Pink × P.G. Violet (P₄x P₅ and P.G. Violet × P.G. White (P₅x P₆) recorded significant sca effects for majority of yield attributes, whereas Kamini × P.G. Violet (P₁ × P₅) and Kamini × P.G. White (P₁ × P₆) for earliness. These cross combinations were recommended for exploitation of heterosis on commercial scale. The combinations with high sca effects involved high × low, low × high and low × low combiners which indicated predominance of non-additive gene action for yield and major yield attributes.